b3

NB: b3 is currently experimental, the API may change without warning.

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b3 helps you compare two Git revisions, typically main and a branch, to understand how your changes affect performance. It is designed for CI but also works during local development. b3 runs the revisions in pairs and uses a Bayesian bootstrap with a small regression to estimate the branch's effect, account for drift and run order, and report the uncertainty around the results.

Usage

b3 --baseline main --candidate HEAD --repetitions 30 --output-dir benchmark/ -- Rscript benchmark.R

Run b3 --help for the full set of options.

Output

Each run writes to --output-dir:

• config.json: run's parameters and resolved revisions.
• benchmark.log: one JSON line per individual run.
• measurements.csv: paired baseline/candidate timings.
• posterior.csv: Bayesian bootstrap draws.
• report.txt: human-readable summary.

License

Dual licensed under either of Apache License, Version 2.0 or MIT license at your option.